<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>网站后台系统</title>
</head>

<frameset rows="20%,*">
    <frame src="top.html"/>
    <frameset cols="20%,*">
        <frame src="left.html"/>
        <frame name="right"/>
    </frameset>
</frameset>
</html>